1. Field of the Invention
The present invention relates to an apparatus for measuring living body impedance for a person and for producing information effective for health care such as body fat percentage, amount of body water and the like. More particularly the present invention relates to a living body impedance measuring apparatus comprising a dividable housing that can be divided into two housing sections for freely setting the distance between the electrodes mounted thereon.
2. Description of the Prior Art
In the past, various types of body fat measuring apparatus, known as a kind of living body impedance measuring apparatus, have been proposed for measuring the living body impedance and for producing corpulence information such as body fat percentage that is a factor indicating a possibility for adult noncommunicable disease.
Among those, one typical apparatus currently available is a compact type body fat measuring apparatus. This compact type measuring apparatus comprises a measuring means, an arithmetic means, an input means and a display means enclosed within a housing, and several current feeding and measuring electrodes mounted on a front and a rear sides of the housing. Also known in the art and has been put into the market before said compact type apparatus is such body fat measuring apparatus that includes an integral weight meter and measures the impedance between both feet of a person. In addition, a body fat measuring apparatus that measures the impedance between both hands of a person while grasping a handle with both hands has also been known in the art before said compact type apparatus. However, those body fat measuring apparatus known in the art before said compact type apparatus are only effective for measuring the impedance between predetermined parts of a human body. In contrast thereto, said compact type body fat measuring apparatus is significantly advantageous in that it can measure the impedance between one of the hands and any one of the parts of the human body. (Refer to TOKUKAIHEI No.11-19059.)
However, said compact type body fat measuring apparatus suffers from such problem that, because of the fact that a person under test must act also as an operator for the apparatus, it is difficult for a handicapped person such as a patient keeping in bed to perform the measurement.
In addition, even in case of a normal person, to measure the impedance between one of the hands and one of the feet, for example, the person must take an unnatural pose, such as to bend his body, which causes an additional burden to the person. This may also produce an unstable condition for muscle and fat in the body, resulting in erroneous measurement.
Furthermore, because of the construction in which one of the hands must be used as a reference, the compact type measuring apparatus can not handle such case that the measurement should be performed between any two points on an abdominal region of the person for estimating body fat percentage.
The compact type measuring apparatus is also defective in that during the time for measuring the impedance between one of the hands and an abdomen of the person the person can not monitor the progress of measurement because of a display unit directed outside the view field of the person.
Furthermore, because of the measurement performed between one of the hands and any one of the parts of the body, rather than between predetermined parts such as both feet and both hands, the person can not see what part of the body is now being measured by the apparatus. It may happen that the person misunderstands the part of the body for measurement.
In view of the above an object of the present invention is to provide a new and improved living body impedance measuring apparatus that can solve the problems of the prior art compact type body fat measuring apparatus, as described above.
In order to achieve such object the present invention provides a dividable apparatus for measuring living body impedance in which a first housing section having a first current feeding electrode and a first measurement electrode mounted thereon can physically be separated from a second housing section having a second current feeding electrode and a second measurement electrode mounted thereon, but said first and second housing sections are kept electrically connected to each other via an electric cable. Therefore it is possible to freely set the distance between the electrodes mounted on the first and second housing sections for the measurement. This is effective in that even in case where a person under test is a handicapped person keeping in bed an attendant or assistant person can divide the apparatus into the first and second housing sections and hold them on the parts of the person under test for measurement.
According to an embodiment of the present invention the second housing section is provided with the second current feeding electrode and the second measurement electrode mounted on the same surface thereof. This allows the second housing section to contact with any part of the person for measurement. In particular even in case where a normal person performs the measurement of impedance between one of the hands and any other part of the body there is no need for the person to take unnatural pose such as to bend his body. This assures to produce highly precise measurement result.
According to another embodiment of the present invention the first housing section is provided with the first current feeding electrode and the first measurement electrode mounted on the same surface thereof. In this embodiment the first housing section can be contact with any part of the body for measurement. This allows for the apparatus to handle such case that the measurement of the impedance is limited only to an abdominal region of the person.
According to further embodiment of the present invention the first housing section is provided with the first current feeding electrodes and the first measurement electrodes mounted on a plurality of surfaces thereof. This can make possible for the display unit on the first housing section to be directed toward the person under test within his view field. Therefore the person under test can perform the measurement, while monitoring the progress in measurement.
According to yet further embodiment of the present invention the second housing section is provided with the second current feeding electrodes and the second measurement electrodes mounted on a plurality of surfaces thereof In this embodiment any suitable one of the electrode-mounted surfaces can be selected to suit to the part of the body to be measured.
In addition the present invention provides a guidance information on the display unit for indicating what part of the body is now measured by using names of that part or legend showing that part.